Bulimia nervosa

Bulimia nervosa is an eating disorder that involves repeated binge eating followed by purging the body of calories to avoid gaining weight. The person who has bulimia has an irrational fear of gaining weight and a distorted body image. Bulimia nervosa can have potentially fatal health consequences. .

Bulimia is an eating disorder whose main feature is eating an unreasonably large amount of food in a short time, then following this binge by purging the body of calories. Purging is most often done by self-induced vomiting, but it can also be done by laxative, enema, or diuretic abuse. Alternately, some people with bulimia do not purge but use extreme exercising and post-binge fasting to burn calories. This can lead to serious injury. Nonpurging bulimia is sometimes called exercise bulimia. Bulimia nervosa is officially recognized as a psychiatric disorder in the Diagnostic

and Statistical Manual for Mental Disorders Fourth Edition-Text Revision (DSM-IV-TR)published by the American Psychiatric Association.

Bulimia nervosa is diagnosed when most of the following conditions are present:

Repeated episodes of binge eating followed by behavior to compensate for the binge (i.e. purging, fasting, over-exercising). Binge eating is defined as eating a significantly larger amount of food in a limited time than most people typically would eat.

Binge/purge episodes occur at least twice a week for a period of three or more months.

The individual feels unable to control or stop an eating binge once it starts and will continue to eat even if uncomfortably full.

The individual is overly concerned about body weight and shape and puts unreasonable emphasis on physical appearance when evaluating his or her self-worth.

Bingebingeinging and purging does not occur exclusively during periods of anorexia nervosa.

Many people with bulimia will consume 3,000-10,000 calories in an hour. For example, they will start out intending to eat one slice of cake and end up eating the entire cake. One distinguishing aspect of bulimia is how out of control people with bulimia feel when they are eating. They will eat and eat, continuing even when they feel full and become uncomfortable.

Most people with bulimia recognize that their behavior is not normal; they simply cannot control it. They usually feel ashamed and guilty over their binge/purge habits. As a result, they frequently become secretive about their eating and purging. They may, for example, eat at night after the family has gone to bed or buy food at the grocery store and eat it in the car before going home. Many bulimics choose high-fat, high-sugar foods that are easy to eat and easy to regurgitate. They become adept at inducing vomiting, usually by sticking a finger down their throat and triggering the gag reflex. After a while, they can vomit at will. Repeated purging has serious physical and emotional consequences.

Many individuals with bulimia are of normal weigh, and a fair number of men who become bulimic were overweight as children. This makes it difficult for family and friends to recognize that someone suffering from this disorder. People with bulimia often lie about induced vomiting and laxative abuse, although they may complain of symptoms related to their binge/ purge cycles and seek medical help for those problems. People with bulimia tend to be more impulsive than people with other eating disorders. Lack of impulse control often leads to risky sexual behavior, anger management problems, and alcohol and drug abuse.

A subset of people with bulimia also have anorexia nervosa. Anorexia nervosa is an eating disorder that involves self-imposed starvation. These people often purge after eating only a small or a normal-sized portion of food. Some studies have shown that up to 60% of people with bulimia have a history of anorexia nervosa.

Dieting is usually the trigger that starts a person down the road to bulimia. The future bulimic is very concerned about weight gain and appearance, and may constantly be on a diet. She (most people with bulimia are female) may begin by going on a rigorous low-calorie diet. Unable to stick with the diet, she then

KEY TERMS

Diuretic—A substance that removes water from the body by increasing urine production.

Neurotransmitter—One of a group of chemicals secreted by a nerve cell (neuron) to carry a chemical message to another nerve cell, often as a way of transmitting a nerve impulse. Examples of neurotransmitters include acetylcholine, dopamine, serotonin, and norepinephrine.

Obsessive-compulsive disorder—A psychiatric disorder in which a person is unable to control the desire to repeat the same action over and over.

eats voraciously far more than she needs to satisfy her hunger, feels guilty about eating, and then exercise or purges to get rid of the unwanted calories. At first this may happen only occasionally, but gradually these sessions of bingeing and purging become routine and start to intrude on the person’s friendships, daily activities, and health. Eventually these practices have serious physical and emotional consequences that need to be addressed by healthcare professionals.

Bulimia nervosa is primarily a disorder of industrialized countries where food is abundant and the culture values a thin appearance. Internationally, the rate of bulimia has been increasing since the 1950s. Bulimia is the most common eating disorder in the United States. Overall, about 3% of Americans are bulimic. Of these 85–90% are female. The rate is highest among adolescents and college women, averaging 5–6%. In men, the disorder is more often diagnosed in homosexuals than in heterosexuals. Some experts believe that number of diagnosed bulimics represents only the most severe cases and that many more people have bulimic tendencies, but are successful in hiding their symptoms. In one study, 40% of college women reported isolated incidents of bingeing and purging.

Bulimia affects people from all racial, ethnic, and socioeconomic groups. The disorder usually begins later in life than anorexia nervosa. Most people begin bingeing and purging in their late teens through their twenties. Men tend to start at an older age than women. About 5% of people with bulimia begin the behavior after age 25. Bulimia is uncommon in children under age 14.

Competitive athletes have an increased risk of developing bulimia nervosa, especially in sports where weight it tied to performance and where a low percentage of body fat is highly desirable. Jockeys, wrestlers, bodybuilders, figure skaters, cross-country runners, and gymnasts have higher than average rates of bulimia. People such as actors, models, cheerleaders, and dancers who are judged mainly on their appearance are also at high risk of developing the disorder. This same group of people is also at higher risk for developing anorexia nervosa. Some people are primarily anorexic and severely restrict their calorie intake while also purging the small amounts they do eat. Others move back and forth between anorectic and bulimic behaviors.

Bulimia nervosa is a complex disorder that does not have a single cause. Research suggests that some people have a predisposition toward bulimia and that something then triggers the behavior, which then becomes self-reinforcing. Hereditary, biological, psychological and social factors all appear to play a role.

Causes

Heredity. Twin studies suggest that there is an inherited component to bulimia nervosa, but that it is small. Having a close relative, usually a mother or a sister, with bulimia slightly increases the likelihood of other (usually female) family members developing the disorder. However, when compared other inherited diseases or even to anorexia nervosa, the genetic contribution to developing this disorder appears less important than many other factors. Family history of depression, alcoholism, and obesity also increase the risk of developing bulimia.

Biological factors. There is some evidence that bulimia is linked low levels of serotonin in the brain. Serotonin is a neurotransmitter. One of its functions is to help regulate the feeling of fullness or satiety that tells a person to stop eating. Neurotransmitters are also involved in other mental disorders such as depression that often occur with bulimia. Other research suggests that people with bulimia may have abnormal levels of leptin, a protein that helps regulate weight by telling the body to take in less food. Research in this area is relatively new, and the findings are still unclear.

Social factors. The families of people who develop bulimia are more likely to have members who have problems with alcoholism, depression, and obesity. These families also tend to have a high level of open conflict and disordered, unpredictable lives. Often something stressful or upsetting triggers the urge to diet stringently and then begin binge/purge behaviors. This may be as simple as a family member as teasing about the person’s weight, nagging about eating junk food, commenting on how clothes fit, or comparing the person unfavorably to someone who is thin. Life events such as moving, starting a new school, and breaking up with a boyfriend can also trigger binge/purge behavior. Overlaying the family situation is the false, but unrelenting, media message that thin is good and fat is bad; thin people are successful, glamorous, and happy, fat people are stupid, lazy, and failures.

Diagnosis is based on several factors including a patient history, physical examination, the results of laboratory tests, and a mental status evaluation. A patient history is less helpful in diagnosing bulimia than in diagnosing many diseases because many people with bulimia lie about their bingeing and purging and their use of laxatives, enemas, and medications. The patient may, however, complain about related symptoms such as fatigue or feeling bloated. Many people with bulimia express extreme concern about their weight during the examination.

A physical examination begins with weight and blood pressure and moves through the body looking for the signs listed above. Based on the physical exam and patient history, the physician will order laboratory tests. In general these tests will include a complete blood count (CBC), urinalysis, and blood chemistries (to determine electrolyte levels). People suspected of being exercise bulimic may need to have x rays to look for damage to bones from over-exercising.

Several different evaluations can be used to examine a person’s mental state. A doctor or mental health professional will assess the individual’s thoughts and feelings about themselves, their body, their relationships with others, and their risk for self-harm.

Treatment choices depend on the degree to which the bulimic behavior has resulted in physical damage and whether the person is a danger to him or herself. Hospital impatient care may be needed to correct severe electrolyte imbalances that result from repeated vomiting and laxative abuse. Electrolyte imbalances can result in heart irregularities and other potentially fatal complications. Most people with bulimia do not require hospitalization. The rate of hospitalization is much lower than that for people with anorexia nerv-osa because many bulimics maintain a normal weight.

Day treatment or partial hospitalization where the patient goes every day to an extensive treatment program provides structured mealtimes, nutrition education, intensive therapy, medical monitoring, and supervision. If day treatment fails, the patient may need to be hospitalized or enter a full-time residential treatment facility.

Drug therapy helps many people with bulimia. Selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine (Prozac) and sertraline (Zoloft) have been approved by the United States Food and Drug Administration (FDA) for treatment of bulimia. These medications increase serotonin levels in the brain and are thought to affect the body’s sense of fullness. They are used whether or not the patient shows signs of depression. Drug treatment should always be supplemented with psychotherapy. (see Therapies below).

Other drugs are being explored for use in the treatment of bulimia. Individuals with bulimia interested in entering a clinical trial at no cost can find a list and description of clinical trials currently enrolling volunteers at http://www.clinicaltrials.gov.

A nutrition consultant or dietitian is part of the team needed to successfully treat bulimia. These professionals usually do a dietary review along with nutritional counseling so that the recovering bulimic can plan healthy meals and develop a healthy relationship with food.

Medical intervention helps alleviate the immediate physical problems associated with bulimia. Medication can help the person with bulimia break the binge/purge cycle. However drug therapy alone rarely produces recovery. Psychotherapy plays a major role helping the individual with bulimia recover from the disorder. Several different types of psychotherapy are used depending on the individual’s situation. Generally, the goal of psychotherapy is help the individual change his or her behavior and develop a healthy attitude toward their body and food.

Some types of psychotherapy that have been successful in treating people with bulimia are listed below.

Cognitive behavior therapy (CBT) is designed to confront and then change the individual’s thoughts and feelings about his or her body and behaviors toward food, but it does not address why those thoughts or feelings exist. Strategies to maintain self-control may be explored. This therapy is relatively short-term. CBT is often the therapy of choice for people with bulimia, and it is often successful at least in the short term.

Interpersonal therapy is short-term therapy that helps the individual identify specific issues and problems in relationships. The individual may be asked to look back at his or her family history to try to recognize problem areas and work toward resolving them. Interpersonal therapy has about the same rate of success in people with bulimia as CBT.

Family and/or couples therapy is helpful in dealing with conflict or disorder that may be a factor in triggering binge/purge behavior at home.

Supportive-expressive therapy or group therapy may be helpful in addition to other types of therapy.

The long-term outlook for recovery from bulimia is mixed. About half of all bulimics show improvement in controlling their behavior after short-term interpersonal or cognitive behavioral therapy with nutritional counseling and drug therapy. However, after three years, only about one-third are still doing well. Relapses are common, and binge/purge episodes and bulimic behavior often comes and goes for many years. Stress seems to be a major trigger for relapse.

The sooner treatment is sought, the better the chances of recovery. Without professional intervention, recovery is unlikely. Untreated bulimia can lead to death directly from causes such as rupture of the stomach or esophagus. Associated problems such as substance abuse, depression, anxiety disorders, and poor impulse control also contribute to the death rate.